Lord Of The Rings - The Return of The King cheats and cheat codes for Gamecube

Pause the game play, then press L + R and press the following 
button combinations:

Multiplayer experience share: Down, A, A, A
Multiplayer health share: Y, Up, B, B
Infinite Multiplayer respawns: X, B, Up, X

Get all upgrades (need to completed game once): Up, Down, Y, B
Always Devasting (need to complete game once): Y, Up, Y, Down
Unlimited Missiles (need to complete game once): B, B, Down, X
Invulnerable (need to complete game once): B, X, B, Up
Perfect Mode (need to complete game once): X, Down, Y, A
Enemy Debug Mode (need to complete game once): Down, X, Up, B
Refill Health (need to complete game once): B, B, X, X
Unlock all Interviews (once): A, B, A, Up

Aragorn cheats:  
+1000 xp: Up, B, Y, A
Level 2 Skills: X, Y, A, Y
Level 4 Skills: Down, B, X, B
Level 6 Skills: X, Y, B, B
Level 8 Skills: Up, B, Y, Up
Three-hit Combo: B, Down, X, Up
Four-hit Combo: Up, B, Y, Down
Special Abilities: Down, X, Y, Y
Restore Missiles (once): Y, B, B, Y

Faramir cheats: 
Unlock Faramir to play (once): A, A, Y, Y
+1000 xp: B, Y, Up, B
Level 2 Skills: A, B, A, Down
Level 4 Skills: A, A, B, B
Level 6 Skills: Y, A, Down, X
Level 8 Skills: X, Down, Down, Down
Three-hit Combo: B, Y, Up, Y
Four-hit Combo: A, B, Up, A
Special Abilities: Up, B, X, Up
Restore Missiles (once): Y, Up, A, A

Frodo cheats: 
Unlock Frodo (once): Y, X, X, X
+1000 xp: Down, Y, Up, Down
Level 2 Skills: Y, Up, Down, X
Level 4 Skills: Y, Up, X, Down
Level 6 Skills: Down, Down, A, Y
Level 8 Skills: X, X, Down, Down
Three-hit Combo: B, Down, Y, B
Four-hit Combo: Down, B, Down, X
Special Abilities: Y, A, Down, A
Restore Missiles (once): Y, Y, Y, X
Unlock Frodo #2 (once): X, B, B, A

Gandalf cheats: 
+1000 xp: X, Y, Up, Down
Level 2 Skills: Down, Y, A, Y
Level 4 Skills: Y, Up, B, A
Level 6 Skills: Y, Y, A, Up
Level 8 Skills: X, B, Down, Down
Three-hit Combo: Down, A, Y, Down
Four-hit Combo: Down, Y, Up, X
Special Abilities: Up, Down, Y, X
Restore Missiles (once): Y, Down, A, B

Gimli cheats: 
+1000 xp: X, X, Y, A
Level 2 Skills: Up, X, B, B
Level 4 Skills: Y, B, Down, Up
Level 6 Skills: Down, Y, Down, B
Level 8 Skills: A, X, Down, B
Three-hit Combo: Up, B, X, B
Four-hit Combo: Y, B, Up, A
Special Abilities: X, B, A, X
Restore Missiles (once): X, X, X, A

Legolas cheats: 
+1000 xp: A, Y, Up, A
Level 2 Skills: B, B, X, B
Level 4 Skills: Down, Down, A, A
Level 6 Skills: Down, X, Up, Down
Level 8 Skills: B, Up, Up, Down
Three-hit Combo: B, Y, Y, X
Four-hit Combo: A, X, Y, B
Special Abilities: Y, X, A, X
Restore Missiles (once): Y, Y, Y, Down

Merry cheats: 
Unlock Merry (once): A, Down, Down, A
+1000 xp: Down, Down, B, A
Level 2 Skills: X, Down, B, B
Level 4 Skills: B, A, X, Down
Level 6 Skills: Down, Down, B, Y
Level 8 Skills: Down, Y, A, B
Three-hit Combo: Y, A, Up, Y
Four-hit Combo: B, A, B, B
Special Abilities: Up, Y, X, X
Restore Missiles (once): B, X, X, Y

Pippin cheats: 
Unlock Pippin: Y, X, B, Down
+1000 xp: Y, A, B, A
Level 2 Skills: Down, A, Down, Up
Level 4 Skills: A, Down, Down, Down
Level 6 Skills: X, Y, X, Y
Level 8 Skills: B, Up, Up, X
Three-hit Combo: Up, Up, B, X
Four-hit Combo: A, A, Down, X
Special Abilities: B, A, X, Y
Restore Missiles (once): Up, X, Down, B

Sam cheats: 
+1000 xp: Y, A, Down, A
Level 2 Skills: X, A, X, Y
Level 4 Skills: Up, Down, B, A
Level 6 Skills: Down, Down, Up, Up
Level 8 Skills: X, X, Y, Y
Three-hit Combo: B, A, X, B
Four-hit Combo: Up, Down, Y, Y
Special Abilities: Up, X, A, X
Restore Missiles (once): A, A, X, A

Unlock Interviews 
Beat the game to unlock the following: 
Palantir of Saruman 
Billy Boyd interview 
Dom Monaghan interview 
Andy Serkis interview 
David Wenham interview